Caffeine, your genes, and heart attacks

Links between caffeine's body-revving abilities and a myocardial infacarction' …

As someone who has, on occasion, gone overboard with my coffee intake, I have experienced the disturbing feeling of my heart racing of its own accord. But past studies have shown no clear connection between caffeine intake and cardiac health, so there seemed to be no reason to worry about major health risks. Until now, that is. Some researchers up in Toronto and their Costa Rican collaborators reasoned that it may not be how much caffeine you consume as much as what your body does with it afterwards.

It seems that the enzyme responsible for breaking down caffeine comes in multiple forms, not all of which are equally efficient. The researchers genotyped over 2,000 individuals who had had their first heart attack, as well as about 2,000 healthy controls. As detailed in a summary of these results, those who metabolize caffeine slowly increased their risk of heart attacks by about 35 percent with just two to three cups of coffee a day. Going to four cups or more shot it up to 64 percent. Those blessed with two copies of the fast version of the gene had reduced odds of a heart attack at the two-three cup level and, even at four cups, had no increased risk.

Now if you'll excuse me, I'm off to genotype the Managing Editor to see if it's safe for him to use the caffeinated soap he praised so highly...